Maybe I am the only one that does this, but I would venture to guess I tip over on purpose twice a year at least. I think it is fun to dump the boat and take a swim for a while.

If your mast is well sealed and you boat is stable, flip it and do some diving off the top hull for a while. It is fun! My crews always say "What if we flip". My rebuttle "Lets find out". More times than not they think it is fun and are no longer scared of the boat.